// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_VIEWS_CONTROLS_MENU_MENU_MODEL_ADAPTER_H_
#define UI_VIEWS_CONTROLS_MENU_MENU_MODEL_ADAPTER_H_

#include <map>

#include "base/callback.h"
#include "base/macros.h"
#include "ui/views/controls/menu/menu_delegate.h"

namespace ui {
class MenuModel;
}

namespace views {
class MenuItemView;

// This class wraps an instance of ui::MenuModel with the
// views::MenuDelegate interface required by views::MenuItemView.
class VIEWS_EXPORT MenuModelAdapter : public MenuDelegate {
public:
    // The caller retains ownership of the ui::MenuModel instance and
    // must ensure it exists for the lifetime of the adapter.
    explicit MenuModelAdapter(ui::MenuModel* menu_model);
    MenuModelAdapter(ui::MenuModel* menu_model,
        const base::Closure& on_menu_closed_callback);
    ~MenuModelAdapter() override;

    // Populate a MenuItemView menu with the ui::MenuModel items
    // (including submenus).
    virtual void BuildMenu(MenuItemView* menu);

    // Convenience for creating and populating a menu. The caller owns the
    // returned MenuItemView.
    MenuItemView* CreateMenu();

    void set_triggerable_event_flags(int triggerable_event_flags)
    {
        triggerable_event_flags_ = triggerable_event_flags;
    }
    int triggerable_event_flags() const { return triggerable_event_flags_; }

    // Creates a menu item for the specified entry in the model and adds it as
    // a child to |menu| at the specified |menu_index|.
    static MenuItemView* AddMenuItemFromModelAt(ui::MenuModel* model,
        int model_index,
        MenuItemView* menu,
        int menu_index,
        int item_id);

    // Creates a menu item for the specified entry in the model and appends it as
    // a child to |menu|.
    static MenuItemView* AppendMenuItemFromModel(ui::MenuModel* model,
        int model_index,
        MenuItemView* menu,
        int item_id);

protected:
    // Create and add a menu item to |menu| for the item at index |index| in
    // |model|. Subclasses override this to allow custom items to be added to the
    // menu.
    virtual MenuItemView* AppendMenuItem(MenuItemView* menu,
        ui::MenuModel* model,
        int index);

    // views::MenuDelegate implementation.
    void ExecuteCommand(int id) override;
    void ExecuteCommand(int id, int mouse_event_flags) override;
    bool IsTriggerableEvent(MenuItemView* source, const ui::Event& e) override;
    bool GetAccelerator(int id, ui::Accelerator* accelerator) const override;
    base::string16 GetLabel(int id) const override;
    const gfx::FontList* GetLabelFontList(int id) const override;
    bool IsCommandEnabled(int id) const override;
    bool IsCommandVisible(int id) const override;
    bool IsItemChecked(int id) const override;
    void SelectionChanged(MenuItemView* menu) override;
    void WillShowMenu(MenuItemView* menu) override;
    void WillHideMenu(MenuItemView* menu) override;
    void OnMenuClosed(MenuItemView* menu, MenuRunner::RunResult result) override;

private:
    // Implementation of BuildMenu().
    void BuildMenuImpl(MenuItemView* menu, ui::MenuModel* model);

    // Container of ui::MenuModel pointers as encountered by preorder
    // traversal.  The first element is always the top-level model
    // passed to the constructor.
    ui::MenuModel* menu_model_;

    // Mouse event flags which can trigger menu actions.
    int triggerable_event_flags_;

    // Map MenuItems to MenuModels.  Used to implement WillShowMenu().
    std::map<MenuItemView*, ui::MenuModel*> menu_map_;

    // Optional callback triggered during OnMenuClosed().
    base::Closure on_menu_closed_callback_;

    DISALLOW_COPY_AND_ASSIGN(MenuModelAdapter);
};

} // namespace views

#endif // UI_VIEWS_CONTROLS_MENU_MENU_MODEL_ADAPTER_H_
